One vertex per element, one color per generator, with an edge from x to x·s.
(2,4)(6,8)(9,10,16,22)(11,19,25,32)(12,18,29,37)(13,17,24,33)(14,21,15,20)(23,35,39,34)(26,40,27,31)(28,38,30,36)(1,2,3,4)(9,11,15,24,16,25,14,13)(10,17,21,32,22,33,20,19)(12,26,30,23,29,27,28,39)(18,34,38,31,37,35,36,40)(5,6,7,8)(9,12)(10,18)(11,23)(13,27)(14,30)(15,28)(16,29)(17,31)(19,35)(20,38)(21,36)(22,37)(24,26)(25,39)(32,34)(33,40)(9,13,14,25,16,24,15,11)(10,19,20,33,22,32,21,17)(12,27,30,39,29,26,28,23)(18,35,38,40,37,34,36,31)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.